Facile fabrication of NiAl-LDH and its application in TPU nanocomposites targets for reducing fire hazards
Xinliang Liu, Xiangtong Ge, Mengru Liu, Keqing Zhou, Qingming Zhu, Depeng Chen, Chunlin Liu, Changlong Wang, Xiuyu Liu, Gang Tang
Abstract
In this study, nickel-aluminium layered double hydroxide (NiAl-LDH) was prepared and characterised. NiAl-LDH was incorporated into thermoplastic polyurethane (TPU) to prepare a series of TPU/NiAl-LDH nanocomposites using solution mixing technology. Thermogravimetric analysis revealed that the addition of NiAl-LDH increased the thermal stability of TPU/NiAl-LDH nanocomposite at high temperatures. Kinetic analysis of the nanocomposites was conducted via the Coats–Redfern method. Thermogravimetric infrared spectroscopy was carried out to investigate gaseous pyrolysis products in degradation process of TPU/NiAl-LDH nanocomposites. TPU/NiAl-LDH nanocomposites showed a significant decrease in CO, hydrocarbon, and aromatic compound intensities than those of pure TPU, indicating that NiAl-LDH can effectively reduce the fire hazard associated with TPU nanocomposites. Furthermore, X-ray photoelectron spectroscopy, scanning electron microscopy, and Raman spectroscopy were used to analyse char residues of TPU/NiAl-LDH nanocomposites. TPU/NiAl-LDH nanocomposites produced a denser char layer with a significantly enhanced graphitisation degree, which inhibited substance and heat transfer during combustion.